Studies will be undertaken to study the kinetic mechanism of the fructose-1,6-bisphosphatase reaction using substrate analogs such as 2,5-anhydromannitol-1,6-bisphosphate, phosphite, and 2-deoxyribose-5-P. Phosphite and 2-deoxyribose-5-P are competitive inhibitors of phosphate and fructose-6-P, respectively when the reverse reaction is studied. We will determine the type of inhibition exhibited by these analogs relative to the substrate that is not competitively inhibited. These experiments should provide information on the enzyme's kinetic mechanism. In addition, studies of both the forward and reverse reaction with 2,5-anhydromannitol-1,6-bisphosphate should provide us with additional information on how fructose-1, 6-bisphosphatase functions as a catalyst. We also plan to study the regulation of the enzyme by the allosteric effector AMP.